Monday, November 10, 2008

Are we running out of Uranium?

Question: Why build new nuclear plants. Arn't we running out of uranium?

Answer: If we take an EROEI apprach and ask, when does the recovery of Uranium cease to be worhwild, we would have to go down to the few parts per million found in ordinary rock before we would start to worry. However if we recovered the thorium content of the rock at the same time, we would have a positive energy return from mining ordinary rock. In addition, uranium can be recovery from sea water with a very favorable EROEI. Not only is the cost of mining uranium from sea water low, but for all practical purposes uranium in sea water is a renewable resource. Uranium mined from sea water will be naturally replaced by uranium from sources in the earth's crust. For all practical purposes both uranium and thorium are renewable resources that will not be exhausted for as long as there are people on earth.

3 comments:

donb
said...

It has always bothered me that nuclear energy is almost always left out of discussions of renewable energy. It is true that the amount of uranium and thorium on the planet is finite, but this is a red herring. The (large) amount of materials needed to harness wind and solar energy is also finite!

As pointed out in the posting, the amounts of thorium and uranium that can be recovered for use in efficient reactors are enough to last for as long as mankind might need them. And if people are still around by the time they run short, we will probably have figured out a practical way to get energy from nuclear fusion, giving us millions of years more of plentiful energy.

Even without thorium or uranium breeding technologies, there's enough marine uranium to supply all of the energy for for human civilization for more than 4000 years. With breeding technologies, there's enough uranium and thorium to power our entire planet at three times current energy consumption levels essentially-- forever.

I like to call the most hyped up renewables, namely Wind Turbines and Solar PV or Solar Thermal Power, THE UNSUSTAINABLES. This is because any modern economy with All Energy Inputs supplied by Solar and Wind Power, is not sustainable.

Solar & Wind Cheerleaders conveniently ignore the fact that the bulk of the energy inputs to the Wind & Solar supply chain, use cheap fossil fuels, hydro, waste biomass and nuclear power as energy inputs. When fossil fuels run out or are environmentally unacceptable, an effort to rely on Wind & Solar Energy will lead to economic collapse - and there won't be Wind Turbines or Solar PV in the Fantasyland Ecotopia that will result, maybe windmills to grind the grain of subsistence farmers ( the few million who survive).